Eccentric mount for telescopic gun sights



SRH RM July 7, 1953 F. A. PACHMAYR ECCENTRIC MOUNT FOR TELEscoPIc GUN smHTs Filed Deo. 19, 1949 55 jwzzyz; -59 76 75 Patented July 7, 1953 UNITED ECCENTRIC MOUNT FOR TELESCOPIC GUN SIGHTS Frank A. Pachmayr, Culver City, Calif.

Application December 19, 1949, Serial No. 133,736

, 11 Claims. l

This invention relates to improvements in telescopic sight mounts of the type including a base and a carriage mounted upon said base and, more particularly, to a mount of the aforesaid type which includes adjusting means to permit the longitudinal axis of the telescopic sight to be varied so that said longitudinal axis may be oriented with respect to the bore of a gun with which said mount and said telescopic sight are associated.

Although the popularity and use of telescopic sights as an aid to bringing down game at long distances have increased rapidly during recent years, rifles are conventionally merchandised with no means provided for mounting telescopic sights thereupon. To remedy this deiiciency, telescopic sight mounts are sold which can be aiiixed to a rifle.

Obviously, the task of securing a telescopic sight mount to a gun requires great precision in order that the longitudinal axis `of the telescopic sight, when positioned in the mount, be properly oriented with respect to the bore of the gun With which it is associated. In the process of securing the mount to the gun, it is generally necessary to drill a plurality of holes in the receiver of the gun to permit the base of the mount to be affixed to said receiver. Drill jigs are frequently provided to facilitate the drilling of the holes in the receiver and it is necessary to position these jigs upon the receiver with great accuracy to avoid the misalignment of the base of the mount upon the receiver and the consequent misalignment of the telescopic sight With reference to the bore of the gun. Once a conventional telescopic sight mount has been secured to the receiver, nothing can be done to vary the orientation of the mount with respect to the receiver and, therefore, if any errors are made in securing the mount to the receiver of the gun they cannot be subsequently compensated.

It is, therefore, a primary object of my invention to provide a telescopic sight mount having a base and a carriage mounted upon said base which includes adjustment means which permit the varying of the longitudinal axis of the car-- riage With reference to the bore of a gun with which the mount is associated to permit the longitudinal axis of a telescopic sight positioned in the carriage of said mount to be correspondingly varied.

Another object of my invention is the provision of a mount of the aforementioned type for telescopic sights which includes attachment means for pivotally securing the carriage to the base of the mount and adjustment means engageable by said attachment means to permit the varying of the longitudinal axis of the carriage and the sight mounted therein with reference to the longitudinal bore of a gun with which said mount and said sight are associated.

An additional object of my invention is the provision of a telescopic sight mount of the aforementioned type which includes a carriage having adjustment means mounted therein, said adjustment means being engageable by attachment means in the base of the mount and said adjustment means being Variable to permit the Varying of the longitudinal axis of the carriage with respect to the longitudinal axis of the attachment means.

A further object of my invention is the provision of a telescopic sight mount of the aforementioned type including a carriage in which is embodied adjustment means for varying the longitudinal axis of the carriage with respect to the bore of the gun with which said mount is associated, said adjustment means including rotatable socket and pin means engageable by attachment means positioned in the base of said mount.

A further object of my invention is the provision of a mount for a telescopic sight which has embodied in the carriage thereof adjustment means permitting the varying of the longitudinal axis of the telescopic sight mounted in the carriage, said adjustment means including a socket member and a pin member which are engageable by attachment means in the base of said mount.

An additional object of my invention is the provision of a mount for telescopic sights which has embodied therein adjustment means which ycan be readily varied to permit a corresponding variance in the longitudinal axis of the carriage with respect to the bore of a,y gun with which said mount is associated.

Another object of my invention is the provision of a mount for telescopic sights which has embodied therein adjustment means for varying the longitudinal axis of the carriage with respect to the bore of a gun with which said mount is associated and which can be easily and cheaply manufactured and assembled and sold for a moderate cost.

Other objects and advantages of my invention will be apparent from the following specication and the accompanying drawing, which is for the purpose of illustration only, and in which:

Fig. 1 is a perspective view showing a gun having mounted upon its receiver a telescopic gun sight mount constructed in accordance with my invention;

Fig. 2 is a vertical, partly sectional view taken on the broken line 2-2 of Fig. 1;

Fig. 3 is a longitudinal, partly sectional view taken on the broken line 3-3 of Fig. 2;

Fig. 4'is a fragmentary, partly sectional view taken on the broken line 4--4 of Fig. 3

Fig. 5 is a fragmentary, partly sectional view taken on the broken line 5 5 of Fig. 3;

Fig. 6 is a fragmentary sectional view taken on the broken line 6-6 of Fig. 3; and

Figs. 7, 8 and 9 are schematic views showing the manner in which the longitudinal axis of a sight can be varied with respect to the bore of a gun with which said sight is associated by the use of a mount constructed in accordance with my invention.

Referring to the drawing, and particularly to Fig. 1 thereof, I show a gun I0 upon the receiver I| of which is secured a sight mount I3 constructed in accordance with my invention. The

sight mount I3 includes a base I4 which is exemplied as an attachment plate |5 secured to the side of the receiver I I by means of screws I1, or similar fasteners.

Formed integrally with and positioned adjacent the upper edge of the attachment plate I5 are longitudinal barrels I9 and 20, the longitudinal axes of which are arranged substantially parallel to the bore of the gun I0, for a purpose which will be described in greater detail below. The barrels I9 and 20 serve as housings for the attachment means 22 of the mount which serves to pivotally secure to the attachment plate I5 a carriage 24 adapted to receive a telescopic sight 25 for -rotation between a first, 4operative position over the receiver of the gun and a second, inoperative position to one side of said receiver, as `best seen in Fig. 2 of the drawing.

Longitudinal bores 21 and 28 are provided by the barrels I9 and 20, the inner ends of said bores being sepa-rated from each other by a central space 29. Disposed in the space 29 between the ends of the bores 21 and 28 is a knurled control knob 3|, said control knob having juxtaposed to the periphery thereof a spring ratchet 32 which is secured to the attachment plate I5 by means of screws 33, or similar fasteners. The spring ratchet 32 is adapted to engage the knurls of the control knob 3| and to thus retain the control knob 3| in any one of a plurality of selected positions. A transverse bore 35 is formed in the interior of the control knob 3| andis provided with a plurality of splines 36 adapted to eng-age mating splines 31 formed on the periphery of annular collars 38 and 39, said collars 38 and 39 being formed integrally with an adjusting member 40 which'traverses the bore 35 in the knob 3 I. The rotation of the adjusting member 40 is accomplished by rot-ating the knurled control knob 3| to overcome the restraining action of the spring ratchet 32. A set screw 43 inthe knurled control knob 3| engages the periphery of the adjusting member 40 between the collars 38 and 39 and prevents the lateral shifting of the control knob 3| in reference thereto.

Disposed within the bore 28 of the barrel 20 is a bearing portion 44 cf the adjusting member 40, said bearing portion having a frusto-oonical bearing 45 adapted to engage a frusto-conical seat 46 formed in a bearing member 41 located in the bore 28. Mounted upon the bearing member 41 is an adjustable latch means 49 which is described in my copending application, Serial No. 133,735, filed December 19, 1949.

The opposite end of the adjusting member 40 is constituted by a screw 58 positioned in the bore 21 of the barrel I9 and engaging the threaded bore 52 of a bolt 53, said bolt having a longitudinal at 54 formed on the periphery thereof and engageable by a pin 55 to prevent the rotation of the bolt 53 within the bore 21 when the screw 50 is rotated therein. When the knurled control knob 3| is rotated, it causes the concomitant rotation of the screw 50 of the adjusting member 40 thus causing the concomit-ant extension or retraction of the rounded end 56 of the bolt 53 out of or into the bore 21 for a purpose which will be described in greater detail below.

Pressed into the end of the bore 28 of the barrel 20 is a receptacle member 58 which provides a conical seat 59 for a purpose which will be described in greater de-tail below. It should be noted that the rounded or hemispherical end 56 of the bolt 53 and the conical seat 59 of the receptacle member 58 are formed concentrically with a common axis A-A which is the longitudinal axis of the attachment means 22.

The carriage 24 includes a substantially cylindrical portion 60 which is provided with a longitudinal slot 6| and which provides a longitudinal bore 62 which is for the reception of the housing 63 of the telescopic sight 25, the eyepiece 64 o-f the sight 25 being positioned exteriorly of and adjacent to one end of the carriage 24.

Formed integrally with the cylindrical portion 6U of the carriage 24 are mounting legs 61 which are separated from each other by slots 68. Screws 63, Fig. 2, threadedly engage the legs 61 and traverse the slots 68 soI that the rotation of the screws will cause the widening or narrowing of the slots 68 to cause the concomitant widening or narrowing of the elongated slot 6| of the cylindrical portion 60 of the carriage 24. 'Ihewidening of the longitudinal slot 6| in the cylindrical portion 60 of the carriage 24 permits the insertion into the bore 62 of the housing 63 of the telescopic sight 25 and the narrowing of the slot 6|, as caused by the screws 69 traversing the slot 68 between the legs 61, serves to securely lock the housing 63 of the telescopic sight in the bore 62.

Formed integrally with and joining the lower ends of the mounting legs 61 together are mounting bosses 1D and 1|, the mounting boss 10 having a bore 13 and a counterbore 14 formed therein and the mounting boss 1| having a bore 15 and a counterbore 16 formed therein. The bore 13 and the counterbore 14 and the bore 15 and the counterbore 16 are formed concentrically with the axis A-A which is, as above-indicated, the axis of the bolt 53 and the receptacle member 56.

Positioned in the bore 13 is the shank 11 of a socket member 18, the head 19 of the socket member 18 being located in the counterbore 14. Formed in the head 19 of the socket member 18 is a conical seat 80, the longitudinal axis of which is eccentric with respect to the longitudinal axis A-A. Since the rounded or hemispherical head 56 of the bolt 53 is concentric with the axis A-A, when said head engages the conical, eccentric seat 86 displacement of the mounting boss 10 from the axis A-A occurs, as most clearly shown in Fig. 4 of the drawing, the eccentric axis of the conical seat being indicated by the point B. The socket member 18 is rotatable in the bore 13 and the counterbore 14, and has formed in the shank thereof an annular groove 8| engageable by locking means 82 constituted by a set screw 83 to prevent the rotation of the socket member 18 in the bore 13 and the counterbore 14 after the socket member 18 has been set in a manner to be described in greater detail below.

Formed in the end of the shank 11 of the socket member 18 is a socket 84 which is adapted to receive a conventional tool to permit the rotation of the socket member 18 to accomplish the setting of the eccentric conical seat 80 with reference to the concentric head 56 of the bolt 53.

Rotatably positioned in the bore 15 to the mounting boss 1I is the shank 86 of a pin member 81, said pin member having integrally formed therewith a convex, hemispherical head 88. The axis of the shank 86 is concentric with the axis A-A, but the axis of hemispherical head 88 is eccentric with the axis A-A. The eccentricity of the axis of the hemispherical head 88 of the pin member 81 is best shown in Fig. 5 of the drawing wherein the longitudinal axis A-A of the pin member is represented by the point A and the eccentric axis of the hemispherical head 88 is represented by the point C. As previously indicated, the shank 86 of the pin member 81 is rotatable in the bore 15 to permit the rotation of the eccentric, hemispherical head 88, said shank being provided with an annular groove 89 which is engageable by locking means 90 constituted by a set screw 9| to prevent the rotation of the shank 86 and the hemispherical head 88 after it has been set in a predetermined position. A socket 92 is provided in the end of the shank 86 for reception of a conventional tool to permit the rotation of the shank 86 to accomplish the setting of the head 88.

When a conventional mount is installed upon the receiver of a gun, the gun is dismantled and the barrel and receiver are mounted in a vise or similar tool and bore sighted upon the center a of a target, Figs. 7, 8 and 9, at a distance of about fifty yards. The attachment plate of the base, together with the carriage, is secured to the receiver by a clamp and a drill jig, not shown, is clamped thereover to permit the drilling of the holes in the receiver to receive the screws which fasten the attachment plate to said receiver. Before the holes are drilled in the receiver, the attachment plate must be shifted to bring the center b of the reticle 94 of the telescopic sight 25 on center with the center a of the target, as

best shown in Figs. '7 through 9 of the drawing. Naturally, such positioning of the mount upon the receiver is a painstaking task and occasionally errors occur which cause the center of the reticle to deviate from the center of the target.

When mounting the mount I3 of my invention upon the receiver II of the gun I6, the aboveoutlined conventional procedure is followed but, after the holes have been drilled in the receiver and the screws I1 inserted therein to fasten the attachment plate I5 thereto, the set screws 83 and 3| in the mounting bosses 1 0 and 1I of the carriage are released to permit the free rotation of the socket member 18 and the pin member 81 to accomplish the more accurate orientation of the telescopic sight 25 with the center a of the target, as best shown in Figs. 7 through 9 of the drawing.

Let us assume that the center b of the reticle 94 of the telescopic gun'sight. 25 is to the left and below the center a of the target after the mount I3 has been secured to the receiver II, as shown in Fig. 7 of the drawing. In describing the use of the socket member 18 and the pin member 81 to overcome deviation of the axis of the telescopic gun sight 25 from the center a of the target, lateral deviation will be designated as windage and vertical deviation will be designated as elevation To overcome the windage, a wrench, not shown, is inserted in the socket 84 and the socket member 18 is rotated to cause the lateral shifting of the mounting boss 10 with respect to the longitudinal axis A--A of the bolt 53. In this manner, the center b of the reticle is shifted until it is coincident with a Vertical line drawn through the center a of the target, as illustrated in Fig. 8 of the drawing. The set screw 83 is then urged against the periphery of the shank 11 of the socket member 18 in the region of the annular groove 8| to restrain the socket member 18 against rotational movement in the bore 13.

The elevational deviation of the center b of the reticle from the center a of the target, as indicated in Fig. 8, is corrected by rotating the pin member 81 in the bore 15 to cause the concomitant rotation of the eccentric head 88 in the conical socket 58. As the head 88 is rotated in a proper direction, the mounting boss 1I is elevated to cause the center b of the reticle to coincide with the center a of the target as illustrated in Fig. 9 of the drawing.

Therefore, the adjustment means of the mountl I3 as constituted by the socket member 18 and the pin member 81, are adapted to cooperate with the attachment means 22 and, more specically, the retractable bolt 53 and the receptacle member 58, to correct for deviations in windage and elevation in the telescopic gun sight 25 and to permit the adjustment of the carriage 24 of the mount to bring the center b of the reticle of the gun sight 25 on center with the center a of the target upon which the bore of the gun IIJ has been previously sighted.

Although I have shown and described a preferred embodiment of my invention for the purpose of illustrating the construction and the mode of operation thereof, it is obvious that changes, alterations and modifications may be made in said construction and I, therefore, do not desire to be limited to the specic details of said construction but prefer, rather, to be afforded the full scope of the following claims.

I claim as my invention:

l. A mount for a telescopic gun sight including: a base for securing said mount to a gun; a carriage for mounting said telescopic gun sight for movement between a rst, operative position and a second, inoperative position; attachment means vfor mounting said carriage upon said base; and rotatable, eccentric adjustment means for orienting said carriage upon said base to vary the longitudinal axis of said sight with reference to the bore of said gun, said adjustment means being retained in operative relationship by common, adjustable attachment means interposed between said adjustment means.

2. In a mount for a telescopic gun sight, the combination of: a base for securing said mount to a gun; a carriage for mounting said telescopic gun sight for movement between a first, operative position and a second, inoperative position, said carriage having mounting bosses and openings in said bosses; attachment means for Y mounting said carriage upon said base; and adjustment means mounted in said openings for orienting said carriage upon said base to vary the longitudinal axis of said sight with reference to the bore of said-gun, and common, adjustable attachment means mounted in said base between said openings for maintaining said adjustment means in operative relationship lwith each other.

, 3.` In a mount for a telescopic gun sight, the combination of a base for securing said mount to a gun; a carriage for mounting said telescopic gun sight for movement between a iirst, operative position and a second, inoperative position, said carriage having mounting bosses and openings in said bosses; attachment means for mounting said carriage upon said base; and rotatable adjustment means mounted in said openings for orienting said carriage upon said base to varythe longitudinal axis of said sight with reference to the bore of said gun, said base providing common, adjustable attachment means interposed between said adjustment means for maintaining said adjustment means in operative relationship with each other.`

4. In a mount for a telescopic gun sight, the combination of: a base for securing said mount to a gun; a carriage for mounting said telescopic gun sight for movement -between a rst, operative position and a second, inoperative position, said carriage having mounting bosses and openings in said bosses; a single, longitudinally shiftable attachment means interposed between said bosses for mounting said carriage upon said base; and adjustment means engageable by said attachment means mounted in said openings for orienting said carriage upon said base to vary the longitudinal axis of said sight with reference vto the bore of said gun.

5. In a mount for a telescopic gun'sight, the combination of: a base for securing said mount to a gun; a carriage for mounting said telescopic gun sight for movement between a rst, operative position and a second, inoperative position, said carriage having mounting bosses and openings in said bosses; a single attachment means interposed between said bosses for mounting said carriage upon said base, said attachment means including a retractable bolt adjacent one end of said base and a receptacle adjacent the other end of said base; and adjustment means mounted in said openings for orienting said carriage upon said base to vary the longitudinal axis of said sight with reference to the bore of said gun, said adjustment means including a rotatable socket member for receiving said bolt and a rotatable pin for engaging said receptacle.

6. In a mount for a telescopic gun sight, the combination of: a base for securing said mount to a gun; a carriage for mounting said telescopic gun sight for movement between a rst, operative position and a second, inoperative position, said carriage having mounting bosses and openings in said bosses; a single attachment means interposed between said bosses for mounting said carriage upon said base, said attachment means in-cluding a retractable bolt adjacent one end of said base and a receptacle adjacent the other end of said base; and adjustment means mounted in said openings for orienting said carriage upon said base to vary the longitudinal axis of said sight with reference to the bore of said gun, said adjustment means including a rotatable socket member having an eccentric seat for receiving said bolt and a rotatable pin` having an eccentric head for engaging said receptacle.

7. In a mount for a telescopic gun sight, the

combination of a base for securing said mount x to a gun, said base providing a longitudinal bore having open ends and an intermediate opening located between said ends; acarriage for mounting said telescopic gun sight for movement between a.first, operative position and a second, inoperative position, said carriage having mounting bosses and openings in said bosses, said openings being in substantial register with said open ends of said bore; a single attachment means interposed between said bosses for mounting said carriage upon said base, said attachment means including a retractable bolt adjacent one end of said base and a receptacle adjacent the other end of said base; a single control for actuating said attachment means disposed in said intermediate opening; and adjustment means mounted in said openings for orienting said carriage upon said base to vary the longitudinal axis of said sight 4with reference to the bore of said gun, said adjustment means including a rotatable socket member having an eccentric seat for receiving said bolt and a rotatable pin having an eccentric head for engaging said receptacle, the

actuation of said single control moving said attachment means into or out of engagement with said adjustment means to respectively permit the reinstallation of said carriage on or release from said base without disturbing the adjustment of said adjustment means.

8. In a mount for a telescopic gun sight, the -combination of: a base for securing said mount to a gun, said base including a longitudinal bore having opposite open ends; a carriage for mount- Y ing said telescopic gun sight for movement between a first, operative position and a second, inoperative position, said carriage having mounting bosses and openings in said bosses, said openings beingin substantial register with said ends of said bore; a single attachment means interposed between said bosses for mounting said carriage lupon said base, said attachment means including a retractable bolt adjacent one end of said base and a. receptacle adjacent the other end of said base; a single control for actuating said attachment means on said base; and adjustment means mounted in said openings for orienting said carriage upon said base to vary the longitudinal axis of said sight with reference to the bore of said gun, said adjustment means including a rotatable socket member having an eccentric seat for receiving said bolt and a rotatable pin having an eccentric head for engaging said receptacle, the actuation of said single control moving said attachment means into or out of engagement with said adjustment means to respectively permit the reinstallation of said carriage on or release from said base without disturbing the adjustment of said adjustment means.

9. In a mount for a telescopic gun sight, the combination of: a base for securing said mount to a. gun, said base including a longitudinal bore having opposite open ends; a carriage for mounting said telescopic gun sight for movement between a first, operative position and a second, inoperative position, said carriage having mounting 'bosses and openings in said bosses, said openings being in substantial register with said ends of said bore; a single attachment means disposed in said bore and including a pair of oppositely movable attachment members disposed in said open ends; control means on said base for longitudinally shifting said attachment members; and adjustment means mounted in said openings and engageable -by said members, said adjustment means being rotatable in said openings to shift the axes of said carriage and said members being shiftable from and into engagement with said adjustment means without disturbing said adjustment means.

10. In a gun sight mount, the combination of: a base for securing said mount to a gun, said 'base having a longitudinal bore with open ends; a single attachment means located in said bore and movable toward and away from said ends, said attachment means including a rotatable member for expelling a bolt from one end of said bore and urging a socket toward the other end of said bore, the axes of said rotatable member and bolt being coincident; a carriage having a pair of bosses aligned with the ends of said bore; and rotatable adjustment means secured to said bosses and engageable with said bolt and said socket, said bolt and said socket being withdrawable from engagement with said adjustment means without disturbing the adjustment thereof.

11. In a gun sight mount, the combination of: a base for securing said mount to a gun, said -base having a longitudinal bore with open ends; a

single attachment means located in said bore and movable toward and away from said ends, said attachment means including a rotatable member for expelling a bolt from one end of said bore and urging a socket toward the other end of said bore. the axes of said rotatable member and bolt 10 being coincident; a single control for actuating said rotatable member; a carriage having a pair of 'bosses aligned with the ends of said bore; and rotatable adjustment means secured to said bosses and engageable with said bolt and said socket, said bolt and said socket being withdrawable from engagement with said adjustment means without disturbing the adjustment thereof.

FRANK A. PACHMAYR.

References Cited in the le of this patent UNITED STATES PATENTS Number Name Date 317,460 Joyner May 5, 1885 440,574 Merritt Nov. 11, 1890 786,509 Merritt Apr. 4, 1905 917,799 Saegmuller Apr. 13, 1909 1,083,288 Lowe Jan. 6, 1914 1,702,393 Rumney Feb. 19, 1929 1,865,339 Schilling June 28, 1932 2,248,372 May July 8, 1941 2,255,529 May Sept. 9, 1941 2,451,266 Whittemore Oct. 12, 1948 2,517,274 Baker Aug. 1, 1950 2,571,935 Pachmayr et al. Oct; 16, 1951Y FOREIGN PATENTS Number y Country Date 468,237 Great Britain 1937 700,353 Germany 1940 

